Windshield wiper for automotive vehicles and the like



WITNESS:

May 4, 1954 c. PARKER 2,677,239

WIND-SHIELD WIPER FOR AUTOMOTIVE VEHICLES AND THE LIKE Filed Nov. 24, 1950 I N VEN TOR.

TTORNEY Patented May 4, 1954 WINDSHIELD WIPER FOR- AUTOMOTIVE VEHICLES AND THE LIKE Leland 0. Parker, Elmira, N. Y., assignor to Bendix Aviation Corporation, a corporation of Delaware . Application November 24, 1950, Serial No. 197,394

7 Claims. I

The present invention relates to windshield wipers for automotive vehicles and the like, and more particularly to improved operating and controlling means therefor.

It is an object of the present invention to provide a novel power element for windshield wipers which is eflicient and reliable in operation and simple and economical in construction.

It is another object to provide such a device which is entirely independent of the power plant of the vehicle.

It is another object to provide such a device which exerts only a predetermined force on the wiper blade, so that if the blade is stuck or frozen there is no damage to the operating mechanism.

It is another object to provide such a device in which if the wiper blade sticks, no energy is expended in abortively attempting to move the blade.

Further objects and advantages will be apparent from the following description taken in connection with the accompanying drawing in which:

Fig. l is a semi-diagrammatic illustration of a preferred embodiment of the invention showing the parts in the positions assumed at the startof a stroke of the windshield wiper blade:

Fig. 2 is a section taken substantially on line 2-2 of Fig. 1;

Fig. 3 is a view similar to Fig. 1 showing the parts in their positions at the start of the opposite stroke of the windshield wiper;

Fig. 4 is a detail on a reduced scale showing a side view of the hydraulic motor and windshield wiper mechanism; and

Fig. is a section taken substantially on the line 5--5 of Fig. 2.

In Fig. 1 of the drawing there is illustrated a pair of coaxially arranged solenoids l and 2 traversed by a plunger 3 of magnetic material adapted to be reciprocated by the alternate energization of the solenoids. member 4 is arranged to be traversed by the extended portion 5 of plunger 3, and a lost motion connection indicated at 6 is arranged to transmit the longitudinal motion of the plunger to the yoke. The yoke 4 is provided with a pair of recesses l and 8 into which a spring pressed detent 9 is arranged to project when the recesses come into alignment with the detent at the oppcsite ends of the stroke of the yoke. The detent thus engages and holds the yoke at the ends of its stroke.

Means are provided for retracting the detent by initial movement of plunger 3 so as to release A slidable yokethe yoke and allow it to move with the plunger. As here shown, this means comprises cam projections ll, 12 on the stem 5 of plunger 3 which extend into a slot 10 in the yoke, and are so positioned as to engage the end of the detent 9 and release it from the recesses I, 8 in the yoke,

such releasing movement being permitted by the lost motion connection 6 between the yoke and plunger.

A hydraulic pump cylinder I3 is arranged ad jacent the yoke 4 and is provided with a piston I4 rigidly attached to a piston rod [5 which:

Spring traverses the arms I6, I! of the yoke. means for actuating the piston rod from the yoke is provided in the form of a compression spring 18 located between the arms of the yoke having thrust plates 19, 2| at its ends adapted to be engaged by the yoke arms. Pins 22, 23 fixedly mounted in the piston rod l5 are also adapted to engage the thrust plates I9, 2!, the arms l6, ll being forked to permit the pins to pass freely therethrough.

A hydraulic motor 24 in the form of a segment of a hollow cylinder is connected by conduits 25, 26 to the opposite ends of the pump cylinder I3, and has an operating vane 21 pivotally mounted at 28 on the axis of the cylinder so as to be oscillated by the reciprocation of the piston l4 of the pump.

A valve 29 is located in the conduit 26 for the purpose of regulating the speed of oscillation of Means for selectively energizing the solenoids l, 2 to cause reciprocation of the plunger 3 is provided comprising a battery 34 which is grounded at 35 and connected by the lead 30 to a mova ble contact blade 35 mounted o the end of the piston rod l5. Blade 36 carriesla pair of contacts 31, 38 adapted to engage contacts 39, 4| respectively mounted on a slidable carrier 42 having a limited amount of longitudinal movement, as indicated at 43. The blade 36 also carries a pair of small permanent magnets 44, 45

adapted to engage armatures 46, 41 respectively 3 mounted adjacent contacts 39, 4| so as to hold the contacts closed for an interval during the sliding movement of carrier 42.

Contact 39 is connected by a lead 48 to the solenoid 2, and contact 4! is connected by a lead 49 and switch 50 to the solenoid I; both solenoids being grounded as indicated at to complete their actuating circuits.

In Fig. 1 of the drawing the plunger 3 is shown in its upper position responsive to actuation of the solenoid I by closure of switch 50 and contacts 38, 4|. The yoke 4 is consequently in its upper position in which it is locked by the detent 9. The spring i8 is compressed against the pin 22 in the piston rod by the arm ll of the yoke, which accordingly applies pressure to the liquid in the pump cylinder l3 above the piston Hi. If now the valve 29 is opened to permit passage of liquid through the conduit 26 the vane 21 of the motor 24 will oscillate toward the left and correspondingly move the windshield wiper blade.

The initial upward movement of the piston rod l5 as permitted by the opening of valve 29 opens contacts 38, 4!, thus deenergizing solenoid l. The movement of the motor and wiper blade proceeds by the expansive force of spring [8 until the piston rod 15 reaches the upper end of its stroke, at which time contact 31 engages contact 39, causing energization of solenoid 2. The plunger 3 is thereby drawn downward, its initial movement causing the cam member l2 to raise the detent 9 out of the recess 7 whereupon the plunger draws the yoke 4 downwardly, thus compressing spring l8 against the pin 23 of the piston rod 15, as illustrated in Fig. 3, the yoke being retained in this position by entry of the detent 9 into the recess 8 of the yoke. Downward movement of the piston rod I5 is thus initiated, contacts 39, 31 being held closed for a short period by the attraction of the magnet 44 for the armature 46, thus ensuring completion of the stroke of the yoke member 4. The downward movement of piston l4 consequently reverses the oscillating movement of the motor vane 21 which then proceeds at a speed controlled by the opening of the valve 29.

Due to the almost instantaneous action of the plunger 3, and yoke 4 in cooking the spring l8, it will be appreciated that the expenditure of electrical energy is of very short duration. Moreover, if the wiper blade should stick or be frozen, the solenoid contacts are held open so that no expenditure of electrical energy will take place. If the blade should stick at the end of its stroke with the contacts closed, the cooking action of the spring 18 by closure of the valve switch 29 will energize the corresponding solenoid, but this energization will be of short duration inasmuch as the normal slight amount of leakage around the piston l4 and the vane 21 will permit the contacts to open shortly, after which they will remain open unless the switch 29 is allowed to remain closed for a long period of time. In that case the solenoids will be occasionally energized for a short period, but in no case will they be held closed so as to cause any substantial waste of electrical energy.

Opening the switch 50 by the operator prevents energization of solenoid i so that the wiper is always parked in the position shown in Fig. 1 when it is not in use.

Although but one embodiment of the invention has been shown and described in detail, it will be understood other embodiments are possi- 4 ble and that various changes may be made in the design and arrangement of the parts without departing from the spirit of the invention.

I claim:

1. Operating mechanism for an oscillating member including a slidable plunger, electromagnetic means for reciprocating the plunger, a hydraulic cylinder, a piston slidably mounted therein, a piston rod fixed thereto; means for actuating the piston rod from the plunger including a slidably mounted yoke member, means connecting the yoke member to the plunger, means including a detent for holding the yoke at the ends of its stroke, means including a spring connecting the yoke to the piston rod, and means actuated by the piston rod for controlling said electromagnetic means.

2. Operating mechanism as set forth in claim 1, in which means connecting the plunger to the yoke is so formed as to permit limited lost motion therebetween; and means actuated by movement of the plunger relative to the yoke for releasing the detent so as to permit the yoke to move with the plunger.

3. Operating mechanism as set forth in claim 1 in which the electromagnetic means for reciprocating the plunger comprises a pair of solenoids arranged when energized to draw the plunger in opposite directions, means for selectively energizing the solenoids including a pair of contacts controlling each solenoid, and means actuated by the piston rod for closing one pair of said contacts as it reaches the end of its stroke in each direction.

4. Operating mechanism for windshield wiper comprising a pair of coaxially-arranged solenoids, a magnetic plunger traversing the solenoids, a slidably mounted yoke member, a connection from the plunger to the yoke member for transmitting longitudinal movement thereto, a compression spring between the jaws of the yoke member, a reciprocating rod traversing said jaws having abutments engaging the ends of the spring, and means including contacts actuated by longitudinal movement of the rod for selectively energizing the solenoids to reversely shift the plunger and yoke at the end of each stroke of the rod.

5. An operating mechanism for an oscillating -motor comprising a pair of coaxially arranged solenoids, a magnetic core slidably mounted in the solenoids, a slidable yoke member, means for connecting the yoke for reciprocation with the magnetic core through a predetermined stroke, a pump rod, spring actuating means yieldably connecting the yoke to the pump rod permitting the yoke to complete its stroke irrespective of movement of the pump rod, and means controlled by movement of the pump rod for selectively energizing the solenoids to cause reciprocation of the magnetic core and yoke.

6. An operating mechanism for an oscillating motor as set forth in claim 5 including further means for latching the yoke at the end of its stroke, means for deenergizing the solenoid which moved the yoke into latched position, and means responsive to energization of the other solenoid for releasing the latch and moving the yoke through the opposite stroke.

'7. An operating mechanism for an oscillating motor as set forth in claim 5 in which the means for selectively energizing the solenoids includes a pair of contacts for each solenoid, and means for holding the contacts closed for a predeter- 5 mined portion of the stroke of the pump rod Number caused by closure of the contacts. 1,737,649 1,805,082 References Cited in the file of this patent 1,897,075 5 1,904,955 UNITED STATES PATENTS 2283886 Number Name Date 2,298,474

357,374 Darling et a1. Feb. 8, 1887 507,671 Boeklen Oct. 31, 1893 696,313 Cheatham Mar. 25, 1902 10 1,668,278 Langdon May 1, 1928 Apr. 27, 1943.

6 Name Date Edsall Dec. 3, 1929 Edsall May 12, 1931 Samson Feb. 14, 1933 Schouten Apr. 18, 1933 I-Ienkell May 19, 1942 Ericson et a1. Oct. 13, 1942 OTHER REFERENCES Ser. No. 240,197, Schmidt (A. P. C.) published 

